13
Getting Started,
continued
Adjust counting
settings
The Tali
™
Image-Based Cytometer comes with pre-set parameters to match the
majority of cultured cell types which can be accurately counted without changing
any of the default parameters.
Counting settings
of the Tali
™
Image-Based
Cytometer allows you to adjust the global image analysis parameters for specific or
mixed cell types; you must be determine these settings empirically.
From the Settings screen, you can adjust the following global parameters for
counting:
Sensitivity
refers to the contrast of the objects from the background. Increasing
the sensitivity makes the instrument more sensitive to objects in the bright field,
while decreasing the sensitivity makes the instrument less sensitive and is
useful if there is more debris in the cell sample.
Circularity
is used to determine which objects to include in the measurement
based on their roundness. Increasing the value for circularity requires objects to
be rounder for inclusion in the measurement and may be useful if you need to
distinguish perfectly round cells from more oddly-shaped cells. Decreasing the
circularity allows objects to be less round for inclusion in the measurement and
may be useful if the cell type is not particularly circular or perhaps oddly
shaped.
The default settings for sensitivity and circularity
are 6 and 8, respectively. To adjust the Counting
settings:
1.
Press
Settings
on the touch screen.
2.
The Settings screen is displayed. Move the
slider bar
located under
Sensitivity
to adjust
the sensitivity setting to the desired level.
3.
Move the
slider bar
located under
Circularity
to adjust the circularity setting to the desired
level.
In addition to sensitivity and circularity, you can also adjust the parameters for the
cell size and GFP and/or RFP-fluorescence, which are specific to the assay in use.
For more information, see
Set gates and thresholds
, page 23.
